Learning Objectives for this Presentation:
By the end of the presentation, participants will be able to understand potential limitations of coverage estimated from surveys that rely on household-retained cards and parental recall, and the need for additional information on reliability of these sources.

Background:
Public health programs rely on household-survey estimates of vaccination coverage as a basis for programmatic and policy decisions. In such surveys throughout the world, vaccination status is typically based on documentation of vaccination dates from household-retained vaccination cards, sometimes supplemented by parental recall. Evidence of the validity of estimates derived from these household information sources has not previously been systematically compiled.

Objectives:
Conduct a systematic review to identify and review studies assessing the validity of household sources of vaccination information for coverage estimates.

Methods:
The review included manuscripts published in peer-review journals and grey literature.

Results:
In the United States, several studies have concluded that the validity of estimates derived from household-retained vaccination cards and parental recall is low. These findings led the Centers for Disease Control and Prevention to obtain provider vaccination records for children included in the National Health Interview Survey and the National Immunization Survey, which estimate coverage for U.S. children. However, evaluation of the validity of coverage estimates in other countries has been limited, and most surveys continue to rely exclusively on vaccination cards and parental recall.

Conclusions:
More information is needed regarding the validity of estimates derived from vaccination cards and parental recall in the developing world. Reliability of these sources may vary widely by setting. This study emphasizes the importance of identifying reliable sources of vaccination history information, improving the quality of vaccination records at health facilities in the developing world, and increasing awareness of the potential limitations of vaccination coverage estimated from surveys that rely on household-retained cards and parental recall.